Electric cable



Feb. 4, 1941. w. F. LAMELA ELECTRIC CABLE Filed July 28, 1938 QQSS .ai C@ INVENTOR mi Q({ATTOREY 1 Patented Feb. 4, 19fl1 UNITED STATES PATENT OFFICE ELECTRIC CABLE poration of New Jersey Application lJuly 28, 1938, Serial No. 221,693

2 Claims.

This invention relates to an improvement in electric cables. particularly well adapted for use in buildings, power houses and in ships, etc., my

- improved cable being ilameproof and at the same l time highly moisture-resistant.

In the accompanying drawing:

Fig. 1 shows a single conductor cable embodylng my invention; and

Fig. 2 is a cross section of a multi-conductor 10 cable constructed in accordance with the invention.

Referring to the drawing in detail, and tlrst of all to Fig. 1: 2 designates the cable conductor. Immediately about the conductor I apply an asu bestos layer l, saturated with a ilameproof compound. This layer is applied preferably in the form of a serving of asbestos rovings. The

ilameproof compound with which this layer is saturated may be made by mixing zinc oxide kand calcium carbonate with benzine as a dispersing medium. Such compound is water insoluble, tlameproof and flame-retarding, as well as nonconductive, and it will not decompose under the iniluence of heat or fire to leave a conducting path of carbon, nor will it decompose or react in any way to form a conducting medium.

About the asbestos layer 4 I apply a glass wool layer 0, preferably glass wool rovings. This layer is not treated with i'lameproof compound, so as to promote and insure fusion of the glass when subjected to high temperatures thereby to provide a non-porous electrical insulating layer.

Over the glass layer is applied a ilexible, moisture-resisting, heat-resisting, electric insulating cloth, designated 8. 'I'his is conveniently a cambric cloth treated with a varnish composed of a drying oil such as China-wood oil and a bitumen such as gilsonite. Cambric treated with this material can be cut into tape i'orm and in addition 40 to being moisture-resisting and heat-resisting is an excellent electric insulator suitable for operating temperatures that would be injurious to rubber.

About the tape 8 I apply a layer III of asbestos similar to the layer l and over this layer I apply a layer I2 oi' a polymerized vinyl halide, painted on its exterior with aluminum paint I3. Aluminum braid Il painted with aluminum paint may be applied over .the polymerized vinyl halide layer I2.

In the construction illustrated in Fig. 2 I employ multi-conductors I8 each of which is insulated with asbestos rovings I8 saturated with ilameproof compound. About the asbestos I8 I apply glass wool 20, and over the wool heatresisting, moisture-resisting, insulating tape 22, similar to the tape I referred to in Fig. l. A wall of asbestos 24 saturated with the ilameproof compound is applied over this tape.

The insulated conductors are cabled about a 5 center 2B of asbestos previously treated with a tlameproof compound.

Dry asbestos fillers 2l that have (been treated with the ilameproof compound are added to fill in the interstlces and provide an assembly round lo in cross section:

About this assembly I provide a wall or layer of asbestos 30 saturated with the ilameproof compound above referred to. A tape 32 is then applied about the asbestos 30. 'I'hls tape convl 15 prises a polymerized vinyl halide frictioned into cotton cloth. A Wall or layer 34 of polymerized vinyl halide is applied about the tape 32, its sur' face painted with an aluminum paint 35, after which an aluminum braid 36 is applied to the ex- 20 terior of the cable. This braid is preferably painted with aluminum paint 31.

It will be seen from all of the foregoing that my invention provides a cable construction which is highly nre-resistant and at the same time moisture-resistant, the flameproof compound employed being of such a nature that it will not decompose under the influence of heat or fire to leave a conducting path of carbon and will not decompose or react to form a conducting medium.

It is to be understood that changes may be made in the details of construction and arrangement of parts herein illustrated and described within the purview of my invention.

What I claim iszf' 1. An electric cable comprising in combination an electric conductor, an asbestos layer saturated with a water insoluble, non-conductive llameproof compound incapable of being decomposed to form a conducting medium about the conductor, a glass wool layer about said asbestos adapted to fuse upon the application of heat to form a non-porous insulating layer, a ilexible, moisture-resisting, heat-resisting, electric insulating fabric about said glass, asbestos saturated with a i'lameproof compound similar to the ilrst mentioned compound albout said fabric and enclosed by a polymerized vinyl halide wall.

2. An electric cable comprising in combination a plurality of electric conductors, an asbestos layer about each conductor, each of said layers being saturated with a water insoluble, nonconductive, ilameproof compound incapable of being decomposed to form a conducting medium, a glass wool layer about the asbestos, a flexible,

conductors are assembled, fillers of asbestos in the spaces between the conductors, a wall of asbestos saturated with nameproof material'similar yto the rst mentioned compound enclosing the assembly, and a polymerized vinyl halide sheath or wall outside said asbestos wall.

WILLIAM l". LAMELA. 

